Remove docked windows entirely in M59.

ash/common/wm/workspace/workspace_window_resizer.h

Index: ash/common/wm/workspace/workspace_window_resizer.h
diff --git a/ash/common/wm/workspace/workspace_window_resizer.h b/ash/common/wm/workspace/workspace_window_resizer.h
index 03b027d977594680fcc344324436eed2e6702c1d..564892181f843f0bcafb428444fb033984b3886e 100644
--- a/ash/common/wm/workspace/workspace_window_resizer.h
+++ b/ash/common/wm/workspace/workspace_window_resizer.h
@@ -18,7 +18,6 @@
 #include "ui/aura/window_tracker.h"
 
 namespace ash {
-class DockedWindowLayoutManager;
 class PhantomWindowController;
 class TwoStepEdgeCycler;
 class WindowSize;
@@ -156,9 +155,6 @@ class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
   bool AreBoundsValidSnappedBounds(wm::WindowStateType snapped_type,
                                    const gfx::Rect& bounds_in_parent) const;
 
-  // Docks or undocks the dragged window.
-  void SetDraggedWindowDocked(bool should_dock);
-
   wm::WindowState* window_state() { return window_state_; }
 
   const std::vector<WmWindow*> attached_windows_;
@@ -215,9 +211,6 @@ class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
   // should attach.
   MatchedEdge magnetism_edge_;
 
-  // Dock container window layout manager.
-  DockedWindowLayoutManager* dock_layout_;
-
   // Used to determine if this has been deleted during a drag such as when a tab
   // gets dragged into another browser window.
   base::WeakPtrFactory<WorkspaceWindowResizer> weak_ptr_factory_;